title: Prediction of chemotherapeutic response in unresectable non-small-cell lung cancer (NSCLC) patients by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2- (4-sulfophenyl)-2H-tetrazolium (MTS) assay.
abstract: BACKGROUND
  Selecting chemotherapy regimens guided by chemosensitivity tests can provide individualized therapies for cancer patients. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H- tetrazolium, inner salt (MTS) assay is one in vitro assay which has become widely used to evaluate the sensitivity to anticancer agents. The aim of this study was to evaluate the clinical applicability and accuracy of MTS assay for predicting chemotherapeutic response in unresectable NSCLC patients.
  
  
  METHODS
  Cancer cells were isolated from malignant pleural effusions of patients by density gradient centrifugation, and their sensitivity to eight chemotherapeutic agents was examined by MTS assay and compared with clinical response.
  
  
  RESULTS
  A total of 37 patients participated in this study, and MTS assay produced results successfully in 34 patients (91.9%). The sensitivity rates ranged from 8.8% to 88.2%. Twenty-four of 34 patients who received chemotherapy were evaluated for in vitro-in vivo response analysis. The correlation between in vitro chemosensitivity result and in vivo response was highly significant (P=0.003), and the total predictive accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for MTS assay were 87.5%, 94.1%, 71.4%, 88.9%, and 83.3%, respectively. The in vitro sensitivity for CDDP also showed a significant correlation with in vivo response (P=0.018, r=0.522).
  
  
  CONCLUSIONS
  MTS assay is a preferable in vitro chemosensitivity assay that could be use to predict the response to chemotherapy and select the appropriate chemotherapy regimens for unresectable NSCLC patients, which could greatly improve therapeutic efficacy and reduce unnecessary adverse effects.
authors.affiliation: Department of Pharmacy, The Affiliated Cancer Hospital of Guangzhou Medical College, Guangzhou, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Chen
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Cheng
authors.forename: Li-Pai
authors.initials: LP
authors.lastname: Chen
authors.forename: Ting-Yuan
authors.initials: TY
authors.lastname: Pang
authors.forename: Xiao-Le
authors.initials: XL
authors.lastname: Wang
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D018287:Carcinoma, Large Cell / Q000188:drug therapy* / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016066:Pleural Effusion, Malignant / Q000188:drug therapy / Q000473:pathology; D011379:Prognosis; D012189:Retrospective Studies; D014407:Tumor Cells, Cultured